Surah An Nahl Tafseer

مَا عِندَكُمْ يَنفَدُ

if you only knew. Whatever you have will be exhausted,

meaning, it will come to an end and will vanish, because it is only there for a certain, limited time.

وَمَا عِندَ اللّهِ بَاقٍ

and what is with Allah will remain.

meaning, His reward for you in Paradise will remain, without interruption or end, because it is eternal and will never change nor disappear.

وَلَنَجْزِيَنَّ الَّذِينَ صَبَرُواْ أَجْرَهُم بِأَحْسَنِ مَا كَانُواْ يَعْمَلُونَ

And to those who are patient, We will certainly grant them their rewards in proportion to the best of what they used to do.

Here the Lord swears, with the Lam of affirmation, that He will reward the patient for the best of their deeds, i.e., He will forgive them for their bad deeds